sgl-project/sglang · error · FileNotFoundError

Image file not found: {image_path}

Error message

Image file not found: {image_path}

What it means

When image_path is given, generate_image switches to the image-edit endpoint and first verifies the file exists on disk, raising FileNotFoundError with the path so you can see exactly which input is missing before any upload is attempted.

Source

Thrown at python/sglang/multimodal_gen/apps/ComfyUI_SGLDiffusion/core/server_api.py:140

        common_params = self._build_image_common_params(
            prompt=prompt,
            size=size,
            n=n,
            response_format=response_format,
            negative_prompt=negative_prompt,
            guidance_scale=guidance_scale,
            num_inference_steps=num_inference_steps,
            seed=seed,
            enable_teacache=enable_teacache,
            background=background,
            output_format=output_format,
            generator_device=generator_device,
        )

        # If image_path is provided, use edit endpoint
        if image_path:
            if not os.path.exists(image_path):
                raise FileNotFoundError(f"Image file not found: {image_path}")

            # Prepare multipart form data for edit
            files: Dict[str, Any] = {}
            data = common_params.copy()

            # Add image file
            files["image"] = (
                os.path.basename(image_path),
                open(image_path, "rb"),
                self._get_content_type(image_path),
            )

            # Add mask file if provided
            if mask_path:
                if not os.path.exists(mask_path):
                    raise FileNotFoundError(f"Mask file not found: {mask_path}")
                files["mask"] = (
                    os.path.basename(mask_path),

View on GitHub (pinned to 0132848349)

Solutions

1. Use an absolute path: os.path.abspath(image_path)
2. Verify existence before calling: os.path.exists(image_path)
3. If the file comes from an earlier step, assert that step succeeded before editing

Example fix

# before
client.generate_image(prompt, image_path="imgs/input.png")

# after
image_path = os.path.abspath("imgs/input.png")
assert os.path.exists(image_path), image_path
client.generate_image(prompt, image_path=image_path)

import os
image_path = os.path.abspath(image_path)
if image_path and not os.path.exists(image_path):
    raise FileNotFoundError(image_path)

def existing_file(p: str | None) -> bool:
    return p is None or (os.path.isabs(p) and os.path.isfile(p))

try:
    client.generate_image(prompt, image_path=image_path)
except FileNotFoundError as e:
    log.warning(f"missing input image {e.filename}; skipping")

When it happens

Trigger: Calling generate_image(..., image_path=p) where p does not exist on the client machine: typo, relative path resolved from a different CWD, or file not yet written.

Common situations: Relative paths breaking when the script runs from another directory, upstream download/save step failed silently, container volume mounts omitting the file.

Understand the failure class

Background: "File not found" and ENOENT errors: why libraries can't find a file that should exist — this error's family across 50 libraries.

Related errors

• Mask file not found: {mask_path}
• Failed to edit image: {str(e)}
• Invalid expert_pack configuration:\n{details}
• Short read for {suffixed}
• Failed to load config from {file_path}: {str(e)}

AI-assisted analysis of sgl-project/sglang@0132848349 (2026-08-28). Data as JSON: /api/errors/61d5451c40690fb5. Report an issue: GitHub.